beep : Java Glossary

Java does not have a built-in set of sounds. It ignores '\a' in console output, though you can use \007. In Java version 1.1 You can make a simple
beep with java.awt.Toolkit.getDefaultToolkit.beep.
I have seen reports that beep does not work properly on some platforms. In
JDK (Java Development Kit)
1.0.2 you can use
System.out.print(\007);
System.out.flush();
You can also play au files. On PCs (Personal Computers)
without a sound card you can play tones on the built-in speaker.